Oscillatory neural activity in olfactory areas of molluscan brains recorded by a 64 electrode planar microarray.
M.A.Harrington1*; A.Gelperin2; J.Witherspoon1; D.F.Camper1; K.Patel1
Society for Neuroscience, 414.9. (2004)
1. Dept Biological Sci., Delaware State Univ, Dover, DE, USA
2. Monell Chem. Senses Ctr., Philadelphia, PA, USA
Planar multi-electrode arrays (the MED 64 system) have been used to record neural activity from slices of rat hippocampus and suprachiasmatic nucleus. The MED 64 system can record field potentials from 64 electrode sites in an 8 x 8 array, and up to four of the electrodes can be used to stimulate the tissue. We have adapted the MED 64 multi-electrode recording array to the study of oscillatory activity in invertebrate olfactory processing centers. Oscillations in local field potential are a common feature of olfactory processing in both vertebrate and invertebrate species, and the propagation of these signals is amenable to study with a multi-electrode array.
We have used the MED 64 to record oscillatory neural activity from central ganglia from the slug, Limax maximus and the snail, Helix aspersa. The procerebral lobes and the surrounding neural tissue along with the olfactory nerves were dissected from the ganglia and completely desheathed. The procerebral lobes and attached olfactory nerves were laid across the MED 64 electrode array and pressed onto the electrodes with a disk of 2% agarose 5 mm in diameter and 2 mm thick. Oscillatory field potential activity was recorded with electrode arrays having either a 100 m or a 75 m inter-electrode distance. Oscillations in local field potential with frequencies ranging from 0.2 Hz to ~ 0.6 Hz were recorded. Superimposing traces recorded from neigboring electrodes showed that waves of depolarization propagate along both the apical to basal axis and perpendicularly across the PC lobe.
Support Contributed By: NSF grants DBI-0320920 and IBN-0315551
